KR20100125198A - Novel resins and photoresist compositions comprising same - Google Patents

Abstract

PURPOSE: A photoresist composition is provided to increase depth of focus isolated line performance, and to ensure excellent pattern collapse of peripheral unit. CONSTITUTION: A photoresist composition comprises a resin including a resin including polycycle and polycyclic ester group. The photoresist composition comprises includes polycycle ester unit. At least one of ester units is an aromatic material. A method for providing a photoregist relief image comprises the steps of: (a) applying a coating layer of a photoresist composition on a substrate; and (b) exposing a photoresist composition layer and developing the photoresist composition coating layer.

Description

Novel resin and photoresist composition containing same {NOVEL RESINS AND PHOTORESIST COMPOSITIONS COMPRISING SAME}

This application claims priority to US Provisional Application No. 61 / 216,660 (filed May 20, 2009) under the provisions of 35 U.S.C. § 119 (e), the contents of which are incorporated herein by reference.

The present invention relates to resins comprising multi-ring, multi-cyclic ester monomers, multi-rings, multi-cyclic ester units, and photoresists comprising such resins. Preferred photoresists are chemically amplified positive-tone compositions comprising the resin and capable of being efficiently imaged with up to 200 nm radiation (eg 193 nm radiation).

Photoresist is a photosensitive film used to transfer an image to a substrate. A coating layer of photoresist is formed on the substrate and then exposed to active radiation through a photomask. The photomask includes portions that are opaque and transparent to the active radiation. Exposure to active radiation results in photoinduced chemical transformations in the photoresist coating, transferring the pattern of the photomask to the photoresist-coated substrate. After exposure, a photoresist is developed to provide a relief image that allows for selective processing of the substrate.

The photoresist may act positively or negatively-acting. Most negative functional photoresists polymerize or crosslink a portion of the coating layer that is exposed to active radiation in the reaction of the photoresist composition with the photoactive compound and the polymerizing agent. Accordingly, the exposed coating part is less soluble in the developer than the unexposed part. The positive functional photoresist is relatively higher in solubility in the developer of the exposed portion than in the unexposed portion (see U.S. 6586157).

While photoresists currently available on the market can be used in a variety of ways, conventional resists present serious problems, particularly in high performance applications, for example in the formation of high resolution sub-half micron and surf quarter micron features.

For example, a problem that persists in conventional resists is a degradation in resolution of “isolated” resist lines or other phases, especially when using positive resists. Typically, developed resist lines or other phases are considered “isolated” when they are more than twice the line width from adjacent resist phases. Thus, for example, when a line appears to be 0.25 μm wide, that is, when the next adjacent resist image is at least about 0.50 μm away from the line, it is considered isolated (not dense). Common resolution problems resulting from isolated lines are rounded tops and undercutting.

One aspect of the present invention is to provide a novel resin containing repeating units comprising multi-ring, multi-cyclic ester units. Another aspect of the present invention is to provide a resin comprising a multi-ring, aromatic ester unit. The resin is particularly useful as a component of the photoresist composition. The poly-cyclic ester resin unit is preferably photoacid-induced cleavage during the lithographic process (exposure, post exposure bake) of the photoresist comprising the resin.

The inventors have found that the lithographic performance of photoresists containing polymers is significantly improved by introducing such ester units into the polymers. In particular, photoresists comprising resins having poly-cyclic ester groups exhibit good pattern collapse at the periphery and increase depth of focus isolated line performance. Relief images of photoresists comprising multi-ring, multi-cyclic ester groups also show excellent resistance to plasma etchants. In addition, preferred poly-cyclic ester groups can act as acid-labile leaving groups with a relatively low activation energy.

While not theoretically supported, large leaving groups (ie, multi-cyclic or aromatic groups) released in lithography processes (ie, photo-induced segments of groups) are exposed by creating more free space in the resist layer. The resist portion significantly improves the desired flowability of the mine, while the large leaving group remaining in the unexposed portion avoids the problem of diffusion of the mine into the exposed resist layer, thereby improving the contrast and lithography results. In other words, leaving groups with relatively high steric hindrance are known to cause the resist to exhibit high dissolution resolution.

In addition, in the presence of secondary branching points (secondary substitutions that do not result in acid-induced removal), the recombination rate of the leaving group is reduced resulting in increased photospeed and / or reduced process temperature (baking temperature after exposure). It is known.

In this specification, a “poly-ring, multi-cyclic ester” compound, unit, group or other structure comprises a plurality of carbon or heteroalicyclic ring groups, at least one of which ring groups being two or more bridged And / or ester moieties, including fused cyclic structures. Carbon alicyclic moieties are usually preferred in which all ring atoms are carbon.

As used herein, a “poly-cyclic aromatic ester” compound, unit, group, or other structure includes cyclic structures in which at least one of the ring groups is two or more bridges and / or fused structures, and typically all ring elements are carbon Ester moieties including multiple alicyclic ring groups.

It is also particularly preferred that the ester group of the present invention is a quaternary carbon or an aromatic ring element where the carbon in the beta position relative to the ester oxygen (eg, the carbon underlined at -C (= 0) OCH ₂ C X ₃ ) is quaternary carbon. . As used herein, “quaternary” carbon refers to a carbon atom having four non-hydrogen substituents (ie, R, R ¹ , R ² and R ³ in CRR ¹ R ² R ³ are the same or different and not hydrogen) . [Reference to Quaternary Carbon: Morrison and Boyd, Organic Chemistry, p. 85 (3rd ed., Allyn and Bacon)].

The beta-carbon or carbon-hetero aliphatic ring atoms, for example, a bridge of carbon (a bridgehead carbon), or alkyl and the other substituents halo (e.g., -C (X) <, wherein X is C _l alkyl _-8 , C _{l - 8} represents alkoxy, halo, etc. the symbol "<" are preferably represents a connection to the other heterocyclic or alicyclic carbon ring atoms). In this specification, the carbon alicyclic group is a non-aromatic cyclic structure in which all ring atoms are carbon. Carbon alicyclic groups of preferred ester units of the present invention include, for example, optionally substituted adamantyl, optionally substituted norbornyl, optionally substituted ethylpenyl, optionally substituted cyclopentane or optionally substituted tricyclo decanyl do. Heteroalicyclic groups herein are non-aromatic cyclic structures in which all ring atoms are not carbon, for example oxygen or sulfur.

In another aspect of the invention, the resin of the invention and a composition comprising the resin further comprises at least one photoacid-labile group separately from the photoacid-labile poly-cyclic aromatic or multi-cyclic ester groups described herein. It is preferable. The photo-labile groups which are additionally present separately also vary, for example, photo-labile esters (eg t-butyl ester) or acetal groups (eg acetal groups provided by vinyl ethers).

Preferably, the multi-ring, multi-cyclic ester group comprises the following formula (I), which may comprise a monomer of formula (IA):

 Formula I

Formula IA

In the above formulas (I) and (IA),

R and R 'are hydrogen or optionally substituted C _{1 -6} alkyl, each independently (e.g., methyl), and, M is an aromatic ring (e. G., Between the carbonyl, such as optionally substituted phenyl, naphthyl, thienyl Click aromatic or heteroaromatic) or a multi-cyclic carbon or heteroalicyclic ring structure, preferably a carbon alicyclic poly-cyclic group (eg, optionally substituted norbornyl, adamantyl), n is from 1 to 1 8, Preferably it is an integer of 1-4.

The M group comprises a carbon alicyclic poly-cyclic group (eg, optionally substituted adamantyl, such as a multi-cyclic, multi-cyclic ester group of formula II, which may include monomers of formula IIA) It is preferable to:

Formula II

Chemical Formula IIA

In Formula II and IIA,

R, R 'and n are as defined in formula I and IA, R ² is a non-hydrogen substituents (e.g. hydroxyl, cyano), optionally substituted alkyl (e.g., optionally substituted C _{1 -8} alkyl), or optionally substituted alkoxy (e. g., an optionally substituted C _{1 - 8} alkoxy group) and; p is an integer of 0-8.

Typically preferred compounds include optionally substituted cyclopentyl or optionally substituted cyclohexyl groups (eg, compounds of Formulas III and IV below):

Formula III

Formula IV

In Formulas III and IV, R ² And p is as defined in formula (II) above.

In another aspect of the invention, preference is given to compounds comprising monomers represented by one or more of the following formulas (V) and (VI), including monomers and resins. Preferably, the moiety is deprotected in the presence of a base (eg 0.26N aqueous alkali photoresist developer) to give an alkali-soluble group (eg carboxylic acid group, sulfonic acid group, amide group, imide group). , Phenol groups, thiol groups, azalactone groups, and hydroxyoxime groups).

Formula V

VI

In Chemical Formulas V and VI,

R ₁ is a straight, branched, monocyclic or polycyclic monovalent carbon having from 7 to 30 carbon atoms which may contain quaternary carbon directly bonded to C1 and which may contain one or more heteroatoms (N, 0 or S). A hydrocarbon group (preferably, R ₁ is monocyclic or polycyclic); n is an integer from 0 to 7; m is an integer from 0 to 2; A represents a divalent linker containing one or more atoms (usually 1 to 10 atoms) of carbon, hydrogen, oxygen, nitrogen, fluorine and / or sulfur.

Preferred monomers include compounds of formula (VII):

Formula VII

In formula (VII), R ₁ is a straight-chain, branched, monocyclic or polycyclic monovalent hydrocarbon group having 7 to 30 carbon atoms that contains a quaternary carbon directly bonded to C1 and may contain one or more hetero atoms; R ₂ is a straight, branched or cyclic monovalent hydrocarbon group of 1 to 6 carbon atoms which may contain one or more hetero atoms (F, N, 0 or S), n is an integer from 0 to 7, m Is an integer of 0 to 2.

Particularly preferred compounds of the present invention include compounds of the formula VIlA:

Formula VIIA

In Formula VIlA, n is an integer of 0 to 7, and R ₄ is the same as R ₂ as defined in Formula VII.

The resins of the invention are non-aromatic units provided by the polymerization of multi-cyclic ester units, in particular, for example, acrylates or optionally substituted cyclic olefins (eg optionally substituted norbornene polymers). In addition, it is preferable to further include a repeating unit. The additional resin unit may also include photo-labile residues such as photo-labile esters or acetal residues. Other preferred resins include hetero-substituted carbocyclic aryl groups (eg, hydroxyl naphthyl groups). In at least certain aspects, particularly preferred resins are those that are substantially free of aromatic moieties or at least aromatic moieties other than hydroxyl naphthyl groups.

Further preferred polymer units include anhydrides such as maleic anhydride or itaconic anhydride; Or by the polymerization of lactones provided by the polymerization of suitable acrylates (eg, acryloxy-norbornane-butyrolactone, etc.).

The photoresist of the invention preferably comprises at least one photoacid generating compound (PAG) as a photoactive component. Preferred PAGs for use in the resists of the present invention include onium salts including iodonium and sulfonium compounds; And non-ionic PAGs (eg, imido sulfonate compounds, N-sulfonyloxyimide compounds; diazo sulfonyl compounds and other sulfone PAGs (eg, a, a-methylenedisulfone, disulfonehydrazine) And disulfonylamine salts), nitrobenzyl compounds, halogenated, in particular fluorinated, non-ionic PAGs.

The photoresists of the invention may also contain blends of resins in which at least one resin contains multi-ring, aromatic and / or multi-cyclic ester groups.

The invention also includes photoimaging components comprising lactone groups and / or resins disclosed herein (which may form relief images in lithographic processes that include patterned exposure to active radiation, optionally heat treatment and development). do.

 The invention also includes a method of forming a relief image comprising a method of forming a high resolution relief image, such as a line pattern (dense or isolated), wherein each line comprises a vertical or essentially vertical side and The width is about 0.40 μm or less, or about 0.25, 0.20, 0.15, or 0.10 μm or less. In the above method preferably the coating layer of the resist of the invention is shortwave radiation, in particular 200 nm or less radiation (especially 193 nm radiation) and high energy radiation of wavelength below 100 nm, or EUV, electron beam, ion beam or It is imaged with other high energy radiation such as x-rays. The invention further encompasses articles made to include substrates, such as microelectronic wafers, on which the photoresist and relief images of the present invention are coated. The present invention also provides a method of making the product.

Other aspects of the present invention are described below.

Representative preferred photoacid-labile ester groups of the present invention include ester units described in the following polymerizable compounds. These compounds are preferred and have a degree of unsaturation suitable for polymerization. The compounds described below can be combined with one another or used in combination with groups other than the groups described below.

As mentioned above, the resins of the present invention may comprise various groups in addition to multi-ring, aromatic and / or multi-cyclic ester units.

In one aspect of the invention, preferred further units of the resins of the invention comprise hetero (particularly hydroxy and thio) -substituted carbocyclic aryl moieties (eg, hydroxy naphthyl groups). Heterosubstituted carbocyclic aryl groups herein refers to carbocyclic wherein the carbocyclic group contains one or more, typically 1, 2 or 3 ring substituents containing hetero atoms (particularly oxygen or sulfur). . In other words, “hetero-substituted” refers to a moiety containing one or more heteroatoms, in particular one or two oxygen and / or sulfur atoms, which are ring substituents of carbocyclic aryl groups.

A hydroxy naphthyl group or other similar term herein refers to a naphthyl group having at least one hydroxy ring substituent. Naphthyl groups may suitably include one or more hydroxy groups, for example two or three hydroxy ring substituents, although typically it is preferred that the naphthyl group contains one hydroxy substituent.

The hetero-substituted carbocyclic aryl units introduced into the resin are naphthyl groups as well as other substituted carbocyclic aryl moieties (e.g., hetero-substituted phenyl, anthracenyl, acenaphthyl, phenanthryl, etc.). It is preferable. Typically, hetero-substituted carbocyclic aryl units comprising multiple fused rings (eg, at least one carbocyclic aryl double or triple fused ring) are hetero-substituted naphthyl, anthracenyl, acetone Naphthyl, phenanthryl, etc. are preferable.

Carbocyclic groups may include various hetero-substituents, with oxygen- or sulfur-containing substituents usually being preferred. For example, preferred heteroaryl of the invention the resin-over between a carbonyl-substituted aryl group, hydroxy (-OH), thio (-SH), alcohol (e.g., hydroxy-C _{1 - 6} alkyl), thio alkyl (e. g., HSC _{1 - 6} alkyl), alkanoyl (e.g., formyl, or an acyl group C _1, such as _{- 6} alkanoylamino), alkyl sulfide (e.g., C _{1 - 6} alkyl sulfide), carboxyl rate (e.g., C _{1 -12} ester), alkyl _ether include an aryl group, or the like (for example, C _{1 8} ether). Preferably, at least one hetero atom of the hetero-containing substituent comprises a hydrogen substituent (eg hydroxy is preferred over alkoxy). In addition, the hetero group has a hetero atom bonded directly to the carbocyclic ring (eg hydroxy or thio ring substituent), or a substituent of the carbon to which the hetero atom is activated (eg -CH ₂ 0H or -CH Ring substituent of ₂ SH), or other primary hydroxy or thio alkyl.

The resins of the present invention may suitably contain a relatively large amount of hydroxy naphthyl units or other hetero-substituted carbocyclic aryl groups. Good etching results can be realized with the use of polymers containing significantly less amounts of hydroxy naphthyl units. For example, the polymers of the present invention may suitably contain less than about 50 or 40 mole percent hetero-substituted carbocyclic aryl units based on the total units of the resin, and even based on the total units of the polymer And less than about 30, 20, 15 or 10 mole percent hetero-substituted carbocyclic aryl units. In fact, the polymers of the present invention may suitably contain about 0.5, 1, 2, 3, 4, 5, 6, 7 or 8 mole percent hydroxy naphthyl units based on the total units of the resin.

Resin of the invention used in photoresist imaged at 193 nm will suitably be substantially free of phenyl or any other aromatic groups other than hetero-substituted carbocyclic aryl units. For example, preferred resins of the present invention used for such short wavelength imaging contain less than about 5 mole percent aromatic groups other than hetero-substituted carbocyclic aryl units, more preferably hetero-substituted carbosai It contains less than about 1 or 2 mole percent aromatic groups other than click aryl units.

The resin of the present invention may also comprise various other units. Preferred additional units include polymerized acrylate or cyclic olefin groups. Particularly preferred units are photo-labile groups such as photoacid-liable esters or acetal groups. For example, the resin may suitably include polymerized tert-butyl acrylate, tert-butyl methacrylate, methyladamantyl acrylate, and / or methyladamantyl methacrylate units. Unless otherwise specified, acrylate groups or compounds referred to herein include substituted acrylate compounds, such as methacrylate compounds.

Preferred polymerized acrylate groups include alicyclic groups. As used herein, the term "alicyclic leaving group" of a resin means: an alicyclic group covalently bonded to a polymer, wherein the polymer comprises a photoresist or photoactive component (especially one or more photoacid generators) When formed as), alicyclic groups can be separated or released from the polymer under acid exposure (ie, the covalent bond with the polymer is broken), and the acid is generally post-exposure heat treated (ie, 90 ° C. or higher). A photoresist coating layer is produced by irradiating the activating radiation (i.e., 193 nm) with a heat treatment for 0.5 minutes, 1 minute or more at a temperature).

The alicyclic acrylate compound includes a vinyl ester, and the ester moiety is an alicyclic group such as methyl adamantyl and the like. Vinyl group suitably may be substituted, and in particular alpha-vinyl, optionally substituted C _{1 -8} alkyl for carbon _{(e.g., -CH 3, CF 3, -CH} 2 OH, -CH 2 CH 2 OH and other halo, Especially fluoro and hydroxy alkyl), and thus include methacrylates.

Preferred polymers include polymers comprising alkyl acrylate units, in particular their acrylate groups containing alicyclic moieties. Preferred polymers are also polymers comprising carbon alicyclic groups such as norbornyl fused to the polymer backbone.

Preferred polymers may also include lactone units such as lactones with polymerized acrylate moieties or other lactones polymerized from other unsaturated molecules. Polymeric units containing alpha-butyrolactone groups are suitable.

Preferred polymers of the invention are copolymers, terpolymers containing 2, 3, 4, or 5 separate repeating units, preferably one or more multi-ring, multi-cyclic ester groups as disclosed herein. ), Tetrapolymers, and pentapolymers.

The polymers of the present invention are preferably used in photoresists imaged at 193 nm and therefore preferably will be substantially free of phenyl or any other aromatic groups other than hetero-substituted carbocyclic aryl units. For example, preferred polymers contain less than about 5 mole percent aromatic groups other than hetero-substituted carbocyclic aryl units, more preferably about 1 or 2 aromatic groups other than hetero-substituted carbocyclic aryl units. Contains less than mole percent.

As mentioned above, the resins of the present disclosure may include photo-labile groups, further multi-ring, multi-cyclic ester groups. Photo-labile groups comprising such additional photo-labile ester groups are often preferred, such as tert-butyl esters or esters containing tertiary alicyclic groups. Such photoacid-labile esters are pendants derived directly from carbon alicyclic, heteroalicyclic or other polymer units (e.g., photoacid-labile groups are of the formula -C (= 0) OR where R is tert-butyl or other Acyclic alkyl group, or tertiary alicyclic group, and directly linked to the polymer unit), or its ester moiety, from a heteroalicyclic or carbon alicyclic polymer unit, for example, optionally an alkylene linkage (e.g., (CH ₂ ) _1-8 C (= 0) OR, where R may be spaced by tert-butyl or other acyclic alkyl group or tertiary alicyclic group). Such photoacid-labile groups may also contain fluorine substitutions where appropriate.

Preferred additional photo-labile ester groups contain tertiary alicyclic hydrocarbon ester moieties. Preferred tertiary alicyclic hydrocarbon ester moieties are adamantyl, norbornyl, ethylpentyl, cyclopentane or tricyclo decanyl moieties. As used herein, “tertiary alicyclic ester group” or other similar term means that tertiary alicyclic carbon is covalently bonded to ester oxygen (ie, —C (═O) O—R′T, where T is alicyclic Tertiary ring carbon of group R '. In at least many cases, preferably the tertiary ring carbon of the alicyclic moiety is covalently bonded to the ester oxygen, as exemplified by the specifically preferred polymers described below. However, tertiary carbon bonded to ester oxygen may also be exocyclic to the alicyclic ring, typically the alicyclic ring being one of the substituents of the outgoing tertiary carbon. In general, the tertiary carbon bonded to the ester oxygen itself is an alicyclic ring itself and / or 1 to about 12 carbons, more generally 1 to about 8 carbons, more generally 1, 2, 3 or 4 carbon atoms. It will be substituted by one, two or three alkyl groups with carbon. The alicyclic group will also preferably not contain aromatic substitution. The alicyclic group may suitably be monocyclic or polycyclic, and in particular may be a bicyclic or tricyclic group.

Preferred cycloaliphatic moieties of the photoacid labile ester groups of the polymers of the invention (eg, TR ′ groups of —C (═O) O—TR ′) have a rather large volume. It has been found that such large volume alicyclic groups can provide improved resolution when used in the copolymers of the present invention.

The polymers of the present invention may also include photoacid-labile groups that do not contain alicyclic moieties. For example, the polymers of the present invention may include photo-labile ester units such as photo-labile alkyl esters. In general, the carboxyl oxygen of the photoacid-labile ester (ie, the underlined carboxyl oxygen: -C (= 0) O ) will be covalently bonded to the quaternary carbon. Generally branched acid-labile esters are preferred, such as t-butyl and -C (CH ₃ ) ₂ CH (CH ₃ ) ₂ .

In this regard, as described above, the polymer used in the photoresist of the present invention may include separate photo-labile groups. That is, the polymer comprises two or more ester groups with distinct ester moiety substitutions, for example one ester having an alicyclic moiety and the other ester having an acyclic moiety such as t-butyl, or the ester and acetal And other photo-labile other functional groups such as, ketal and / or ether.

As described above, various sites of the resin unit may be optionally substituted. "Substituted" substituents are substituted at one or more possible positions, generally for example halogen (particularly F, Cl or Br); Cyano; C _{1 -8} alkyl; C _{1 -8} alkoxy; C _{1 -8} alkylthio; C _{1 -8-alkyl-sulfonyl;} C _{2 -8} alkenyl; C _{2 -8} alkynyl; Hydroxyl; Nitro; By one or more suitable groups such as C _{1 -6} alkanoyl such as alkanoyl is substituted at the 1, 2 or 3-position.

A preferred alkanoyl group is formulas -C (= O) R '' ( wherein, R 'has at least one keto group, such as a' is hydrogen or C _{1 -8-alkyl)} group.

The polymer of the present invention can be prepared by various methods. One suitable method is an addition reaction involving free radical polymerization, for example in the presence of a radical initiator in an inert atmosphere (eg N ₂ or argon), although the reaction temperature is the boiling point of the reaction solvent (if a solvent is used). Depending on the reactivity of the particular reagent used, one may react the monomer selected to provide various units as described above at elevated temperatures, such as about 60 ° C. or higher. Suitable reaction solvents include, for example, halogenated solvents such as tetrahydrofuran or more suitably fluorinated solvents or chlorinated solvents. Appropriate reaction temperatures for any particular system can be readily determined experimentally by one skilled in the art based on the disclosure herein. Various free radical initiators can be used. For example, azo compounds such as azo-bis-2,4-dimethylpentanenitrile can be used. Peroxides, peresterates, peracids and persulfates can also be used. Example 2 follows typical preferred reaction conditions and procedures.

Other monomers that can be reacted to provide the polymers of the invention can be identified by one skilled in the art. For example, to provide photoacid-labile units, suitable monomers include, for example, methacrylates or acrylates containing appropriate group substitutions (e.g. tertiary alicyclic, t-butyl, etc.). . Suitable acrylate monomers having tertiary alicyclic groups for synthesizing polymers useful in the photoresist of the present invention are disclosed in US Pat. No. 6,306,554 to Barclay et al. Maleic anhydride is a preferred reagent to provide fused anhydride polymer units. Vinyl lactones are also preferred reagents, such as alpha-butyrolactone.

The polymers of the present invention will preferably have a weight average molecular weight (Mw) of about 800 or 1,000 to about 100,000, more preferably about 2,000 to about 30,000, more preferably about 2,000 to 15,000 or 20,000, and molecular weight distribution. (Mw / Mn) will be about 3 or less, more preferably about 2 or less. The molecular weight (Mw or Mn) of the polymer of the present invention is suitably determined by gel permeation chromatography.

The polymers of the invention used in the manufacture of chemically-amplified positive-acting photoresists contain a sufficient amount of photogenerated acid labile ester groups to enable resist relief image formation as desired. It must be contained. For example, a suitable amount of such acid labile ester groups will be at least 1 mole percent, more preferably about 2 to 7 mole percent, even more preferably about 3 to 30, 40, 50 or 60 mole percent of the total polymer units. .

As mentioned above, the polymers of the present invention are very useful as resin components in photoresist compositions, especially chemically-amplified positive resists. Photoresists of the invention generally comprise a photoactive component and a resin binding component comprising the polymer described above.

The resin component should be used in an amount sufficient to provide a coating layer of the resist that can be developed with an aqueous alkaline developer.

The resist composition of the present invention also includes a photoacid generator (ie, "PAG") that is suitably used in an amount sufficient to produce a potential image in the coating layer of the resist under exposure to activating radiation. Preferred PAGs for imaging at 193 nm and 248 nm include imidosulfonates, such as compounds of the formula:

Wherein R is camphor (camphor), adamantane, alkyl (i.e., C _{1 -12} alkyl) and fluoro (C _{1 -18} alkyl), or RCF ₂ - (wherein, R is optionally substituted adamantyl tilim) and Same fluoroalkyl.

Preference is also given to triphenyl sulfonium PAG complexed with the aforementioned sulfonate anions, in particular anions such as perfluoroalkyl sulfonates such as perfluorobutane sulfonate.

Other known PAGs can also be used in the resists of the present invention. In particular, for 193 nm imaging, generally preferred PAGs do not contain aromatic groups to provide improved transparency, such as the imidosulfonates mentioned above.

Other suitable photoacid generators for use in the compositions of the present invention are, for example, triphenylsulfonium trifluoromethanesulfonate, (p-tert-butoxyphenyl) diphenylsulfonium trifluoromethanesulfonate, tris sulfonium salts such as (p-tert-butoxyphenyl) sulfonium trifluoromethanesulfonate, triphenylsulfonium p-toluenesulfonate; Nitrobenzyl derivatives such as 2-nitrobenzyl p-toluenesulfonate, 2,6-dinitrobenzyl p-toluenesulfonate and 2,4-dinitrobenzyl p-toluenesulfonate; 1,2,3-tris (methanesulfonyloxy) benzene, 1,2,3-tris (trifluoromethanesulfonyloxy) benzene and 1,2,3-tris (p-toluenesulfonyloxy) benzene Such as sulfonic acid esters; Diazomethane derivatives such as bis (benzenesulfonyl) diazomethane and bis (p-toluenesulfonyl) diazomethane; Glyoxime derivatives such as bis-O- (p-toluenesulfonyl) -α-dimethylglyoxime and bis-O- (n-butanesulfonyl) -α-dimethylglyoxime; Sulfonic acid esters of N-hydroxyimide compounds such as N-hydroxysuccinimide methanesulfonic acid ester and N-hydroxysuccinimide trifluoromethanesulfonic acid ester; And 2- (4-methoxyphenyl) -4,6-bis (trichloromethyl) -1,3,5-triazine and 2- (4-methoxynaphthyl) -4,6-bis (trichloro Halogen-containing triazine compounds such as methyl) -1,3,5-triazine. One or more such PAGs may be used.

Preferred optional additives of the resist of the present invention are added bases, in particular tetrabutylammonium hydroxide (TBAH) or tetrabutylammonium lactate, which can improve the resolution of developed resist relief images. For resists imaged at 193 nm, preferably added bases are lactate salts of tetrabutylammonium hydroxide and various other amines such as triisopropanol, diazabicyclo undecene or diazabicyclononene. The added base is suitably used in relatively small amounts, for example in amounts of about 0.03 to 5% by weight relative to the total solids.

The photoresist of the present invention may also include other optional materials. For example, other optional additives include anti-striation agents, plasticizers, rate enhancers, degradation inhibitors, and the like. Such optional additives may be present in relatively high concentrations, for example in small concentrations in the photoresist composition except for fillers and dyes, which may be present in amounts of about 5 to 30% by weight of the total weight of the dry components of the resist. will be.

The resist of the present invention can be easily prepared by those skilled in the art. For example, the photoresist composition of the present invention may be, for example, 2-heptanone, cyclohexanone, ethyl lactate, ethylene glycol monomethyl ether, ethylene glycol monomethyl ether acetate, propylene glycol monomethyl ether, propylene glycol It can be prepared by dissolving the components of the photoresist in a suitable solvent such as monomethyl ether acetate and 3-ethoxyethyl propionate. Generally, the solids content of the composition varies between about 1 and 35 weight percent of the total weight of the photoresist composition. The resin binder and photoactive component are present in an amount sufficient to provide a film coating layer and latent relief image formation of good quality.

The composition of the present invention is generally used according to known procedures. The liquid coating composition of the present invention is applied to the substrate by spinning, dipping, roller coating or other conventional coating technique. When spin coating, the solids content of the coating solution can be adjusted to provide the required film thickness based on the specific spinning device utilized, the viscosity of the solution, the speed of the spinner and the amount of time allowed for spinning.

The resist composition of the present invention is suitably applied to a substrate commonly used in the process related to the coating of the photoresist. For example, the composition may be applied to a silicon wafer or a silicon wafer coated with silicon dioxide for the manufacture of a microprocessor or other integrated circuit board. The photoresist may be coated on a substrate, for example another coating, such as an organic or inorganic antireflective composition. Aluminum-aluminum oxide, gallium arsenide, ceramics, quartz, copper, glass substrates and the like can also be used as appropriate.

Following the coating of the photoresist on the surface, it is preferably dried by heating to remove the solvent until the photoresist coating is tack free. It is then imaged through the mask in a conventional manner. The exposure is done to a degree sufficient to effectively activate the photoactive component of the photoresist system to produce a patterned image in the resist coating layer, more specifically the exposure energy depends on the components of the photoresist composition and the exposure mechanism, but generally about 1 to 100 mJ / cm ² Range.

As mentioned above, the coating layer of the resist composition of the present invention is preferably photoactivated by short exposure wavelengths, in particular by sub-300 and sub-200 nm exposure wavelengths. As mentioned above, 193 nm is a particularly preferred exposure wavelength. However, the resist composition of the present invention can also be imaged at suitably higher wavelengths. For example, the resins of the present invention are imaged at higher wavelengths of, for example, 248 nm or 365 nm, with suitable PAGs and photosensitizers as needed.

Following exposure, the film layer of the composition is preferably cured at a temperature in the range of about 60 ° C to about 160 ° C. After that, the film is developed. The exposed resist film may be a polar developer, preferably an aqueous based developer, for example a tetra-alkyl ammonium hydroxide solution, preferably a quaternary ammonium hydroxide solution such as 0.26 N tetramethylammonium hydroxide; Various amine solutions such as ethyl amine, n-propyl amine, diethyl amine, di-n-propyl amine, triethyl amine or methyldiethyl amine; Alcohol amines such as diethanol amine or triethanol amine; The use of cyclic amines such as pyrrole, pyridine and the like will result in positive action. In general, the development is in accordance with procedures recognized in the art.

Following development of the photoresist coating on the substrate, the developed substrate can optionally process the resist free portion, for example, by chemically etching or plating the resist free substrate portion according to procedures known in the art. will be. In the manufacture of microelectronic substrates, for example in the manufacture of silicon dioxide wafers, suitable caustics, including gaseous caustics, for example Cl ₂ Or halogen plasma caustic such as chlorine or fluorine based caustic such as CF ₄ / CHF ₃ caustic. After such a process, the resist is removed from the processed substrate using a known stripping process.

All documents mentioned herein are incorporated herein by reference. The following non-limiting examples are for illustrative purposes.

Example 1: ACPMA Monomer Synthesis

ACP-OH (150 g) is dissolved in dry CH ₂ Cl ₂ (0.2 L). Methacryloyl chloride (100 mL) is added. The solution is cooled in a cooling bath. Dry CH ₂ Cl ₂ Dry triethylamine (236 mL) and N, N-dimethylaminopyridine (3 g) solution in (0.2 L) were added dropwise over 4 hours. After dropping, the reaction mixture is slowly warmed up to room temperature and stirred for 3 days. The reaction mixture is cooled in a cooling bath. Water (500 mL) is added dropwise and the mixture is stirred for an additional 15 minutes. The phases are separated. The organic layer is washed with water (1 × 100 mL), HCl (0.3N, 2 × 100 mL), NaHCO ₃ (2 × 100 mL), dried over Na ₂ SO ₄ and concentrated to give a pale yellow solid. Recrystallization in heptane gives ACPMA (109 g) as a white solid.

Example 2 Synthesis of ACPMA / ECHMA / αGBLMA / ODOTMA / HAMA Pentapolymers

The monomer was used in the following amounts: ACPMA: 6.57 gms; ECHMA: 4.2 gms; αGBLMA: 5.9 gms; ODOTMA: 5.5 gms; HAMA: 2.7 gms. This amount of these monomers was dissolved in 15 g of tetrahydrofuran and bubbled with nitrogen. 5 g of tetrahydrofuran and 2.9 gms of V601 initiator were removed into separate flasks. The round bottom flask was fitted with a cooler, nitrogen tube and 5 g of tetrahydrofuran and heated to 70 ° C. The temperature at which the V601 / tetrahydrofuran mixture was added was allowed to return to 70 ° C. The monomer solution was then injected into the flask for at least 3.5 hours and left for 30 minutes. After addition to a 15 ml solution of tetrahydrofuran, it was cooled to room temperature in a cooling bath. The solution was then precipitated with 20 × volume isopropyl alcohol and redissolved in ˜30% tetrahydrofuran and then secondary 20 × volume isopropyl alcohol precipitated. The material was then dried at 45 ° C. in a vacuum oven overnight to yield 17.7 g of a white solid of the title pentapolymer.

Example 3: Photoresist Preparation and Processing of the Invention

The resist of the present invention is prepared by mixing the following components, where the amount is expressed in percent by weight of solids (all components except solvent) and the resist is prepared by mixing the following components having the following amounts.

ingredient amount

0.8347 grams of resin

PAG 0.1314 grams

0.0152 grams of basic additive

Solvent Propylene Glycol Monomethyl Ether Acetate (PGMEA):

7.0756 grams / methyl hydroxybutyrate: 11.79 grams / cyclohexanone: 4.71 grams

In this resist, the resin is the polymer of Example 2 above. PAG is triphenylsulfonium 3-hydroxyadamantyloxycarbonyldifluoromethanesulfonate. The basic additive is dodecyl diethanolamine.

The resin composition prepared is spin coated onto a HMDS gas primed silicon wafer and softbaked on a vacuum hotplate at 110 ° C. for 60 seconds. The resist coating layer is exposed through a photomask at 193 nm and the exposed coating layer is post-exposure baked at 95 ° C. for 60 seconds. The imaged resist layer is then developed by treatment with a 0.26 N aqueous tetramethylammonium hydroxide solution.

In the present invention, the above description is merely for explaining the present invention, it can be seen that modifications and variations of the present invention are affected by the present invention, without departing from the spirit or scope of the present invention as set forth in the claims below. have.

Claims (15)

A photoresist composition comprising a resin comprising a multi-ring, multi-cyclic ester unit. And a resin comprising a multi-ring ester unit, wherein at least one ring of said ester unit is aromatic. The photoresist composition of claim 1, wherein the ester-beta carbons are aromatic or quaternary carbons. The photoresist composition of claim 1, wherein the resin comprises one or more units having the group of formula (I):
Formula I

In Formula I,
M is an aromatic or multi-cyclic carbon or heteroalicyclic ring structure,
n is an integer of 1-5. The photoresist composition of claim 1, wherein the resin comprises one or more units having a group of formula II:
[Formula II]

In Chemical Formula II,
Is _{6-alkyl, -} R and R 'are C ₁ each independently hydrogen or optionally substituted
R ² is the same or different non-hydrogen substituents,
p is an integer from 0 to 8,
n is an integer of 1-5. A film-forming compound having a structural unit comprising a protected alkali-soluble group, wherein the protected site of the protected alkali-soluble group in the unit can be cleaved by the acid action generated from the photoacid generator, Photoresist compositions comprising groups of V and VI:
(V)

(VI)

In Chemical Formulas V and VI,
R ₁ is a straight, branched, monocyclic or polycyclic monovalent hydrocarbon group having 7 to 30 carbon atoms containing quaternary carbon directly bonded to C1 and which may contain one or more hetero atoms;
n is an integer from 0 to 7;
m is an integer from 0 to 2;
A represents a divalent linker containing at least one atom of carbon, hydrogen, oxygen, nitrogen, fluorine and sulfur. 7. The photoresist composition of claim 6, wherein the alkali-soluble group is selected from the group consisting of carboxylic acid groups, sulfonic acid groups, amide groups, imide groups, phenol groups, thiol groups, azalactone groups, and hydroxyoxime groups. . The photoresist composition of claim 1 wherein the resin is a copolymer, terpolymer, tetrapolymer or pentapolymer. The photoresist composition of claim 1, wherein the photoresist is at least one photoacid generator compound and the ester group is photoacid-labile. The photoresist composition of claim 1, wherein the photoresist resin comprises a second photoacid-labile group different from the photoacid-labile ester. a) applying a coating layer of the photoresist composition of claim 1 to a substrate; And
b) exposing the photoresist composition layer to actinic radiation and developing the exposed photoresist composition coating layer,
A method of providing a photoresist relief image. A resin comprising poly-rings, multi-cyclic ester units and / or multi-ring ester units, wherein at least one ring of said ester units is aromatic. 13. The resin of claim 12, wherein the ester beta-carbon is aromatic or quaternary carbon. Optionally polymerizable compounds comprising the structure of formula (I)
(I)

In Formula I,
M is an aromatic or multi-cyclic carbon or hetero alicyclic ring structure,
n is an integer from 1 to 8. An imageable composition comprising the resin or compound according to claim 12.